'O' Rings Called Major Concern in Titan Blast : Rubber Seals Were Like Those on Challenger; Possibility of Sabotage Also Will Be Probed

Three members of the military were admitted to the hospital; two of them were released Friday evening and the third, after being held overnight for examination of "possible" exposure to the fuel, was released Saturday morning.

Groups Voice Alarm

Several farmers and a local peace activist organization voiced alarm Saturday, saying that a weapons and missile center with the potential for major pollution and explosions should not be located close to population centers such as Lompoc (population 26,267), which is about eight miles northeast of the launch site.

Bill Beattie, who grows vegetables and flowers about two miles from the base, said his crops are susceptible to the sort of corrosive clouds released by Friday's explosion, and "even exhaust from a space shuttle can cause tip burns on spinach and asparagus."

"Had the winds been blowing in a different direction Friday, people in Lompoc could have been in real danger," said Bud Boothe, a member of the Vandenberg Action Coalition. But Watkins said the Air Force takes careful precautions before any launch, monitoring weather conditions and wind drift to make sure that if there is any disaster at the base, no population centers will be affected. Rail traffic on the Southern Pacific main line--which passes a few hundred yards from the launch pads--is halted before any launch.

Watkins said that when Friday's explosion occurred, "standard accident response procedures" were followed. They included notification of the Lompoc police and fire departments, the Santa Barbara County fire and sheriff's departments, the California Highway Patrol and the Coast Guard. Several roads on the western edge of the Lompoc Valley were temporarily closed.

Evacuations Limited

As soon as it became apparent that the toxic cloud would pass well to the south of the city, school officials and police in Lompoc were advised that no evacuation would be necessary.

Watkins said that the only off-base evacuations were precautionary--at Jalama Beach, about 10 miles southwest of the launch site, and at Anacapa Island, about 50 miles downwind.

The exact cause of last August's failure of a Titan 34-D after takeoff from Vandenberg remains a mystery despite more than seven months of investigation.

Air Force officials have said only that one of the main liquid fuel engines shut down about two minutes into the flight, but no one has said why. Despite secrecy surrounding the probe, aerospace sources have suggested that the craft was destroyed over the Pacific after the malfunction was discovered.

Louis Sahagun reported from Vandenberg Air Force Base and Eric Malnic from Los Angeles. Times staff writers Miles Corwin in Lompoc and Don Irwin in Washington contributed to this story.